Following the commencement of work on the Colchester Inner Relief Road, a supplementary site investigation was carried out at the Balkerne Hill subway to provide additional information required in order to economise on the foundation costs of the subway. The subway was to be constructed on an area which was formerly gardens of houses fronting onto Balkerne Hill. To the north of the subway is an open area which was a former rubbish tip, marshland. The aerial photos of the site also showed land use nearby 'dating back to Roman times. This could possibly account for the piece of pottery found at a depth of 3.5 metres in borehole 2'. A total of three boreholes were drilled revealing made ground to depths of 2 and 3 metres below the surface. The made ground included rubble, shell and gravel. As previously mentioned, a piece of pottery was found in borehole 2 within a layer of silty sand with gravel and peat. This was possibly also made ground. Beneath the made ground were alluvial deposits of sand, silt, clay and gravel with occasional woody material. These layers overlay the London Clay at depths of between 7 and 8 metres.<1>